Donald Walsh, 30, of Monee, punched his then-girlfriend in the face and choked her at about 3 a.m. on July 25, 2012 at her Mokena home, authorities said. Judge Edward Burmila found him guilty after a bench trial in Will County Circuit Court in Joliet.

Walsh also is charged with threatening the woman during a phone conversation that she secretly recorded a month before the July 25 incident. His next court appearance on that charge is Feb. 18.

Walsh has been on administrative leave without pay since his arrest.

“His conduct in this disrespected the department that he served in,” Burmila said while issuing his verdict. “He brought public disdain on all police officers in general.”

Burmila found Walsh not guilty of a more serious felony charge of aggravated domestic battery for allegedly attempting to strangle the woman.

Burmila said he considered evidence — a surveillance video clip from a Tinley Park bar — that defense attorney Steve Haney had said shows the alleged victim pushed Walsh and struck him several months before the July incident, suggesting why he might have to act in self-defense. Haney also told the judge the injuries suffered by the woman in the July 25 altercation were more consistent with being subdued than with being physically attacked.

But special prosecutor Dave Neal emphasized that the video shows that the woman was escorted calmly out of the bar and did not have to be forcefully subdued. He said evidence showed that her injuries in the July 25 incident were the result of Walsh’s physical abuse and were inconsistent with a claim of self-defense.

No charges were filed in the Tinley Park incident.

Burmila said that even if Walsh initially was defending himself in the July 25 incident, he believed he went too far.